The present invention relates to a lens specifying apparatus for measuring the spectral transmittances of a lens under examination and displaying the measured spectral transmittances.
There are various eyeglass lenses including ones of colored type, anti-surface-reflection type, flaw-free-coating covered type, and UV (ultraviolet ray) cut-off type which cuts off an ultraviolet ray harmful to eyes.
If one of the lenses in the right and left lens frames of eyeglasses is broken, it is desirable to fit a lens of the same type as the unbroken lens in one of the lens frames.
However, it was difficult to know the characteristics of the unbroken lens, i.e., the spectral transmittances thereof at a mere sight of the unbroken lens.
It is therefore an object of the present invention to provide a lens specifying apparatus capable of easily and promptly measuring the spectral transmittances of a lens.
To attain the object, the present invention provides as defined in claim 1 an apparatus including lens measuring means having a measurement optical system for measuring a refractive characteristic of a lens under examination, the apparatus comprising: spectral characteristic measuring means having apart of an optical path in common with the measurement optical system of the lens measuring means and measuring a spectral transmittance of the lens under examination; and
display means for displaying the spectral transmittance of the lens under examination measured by the spectral characteristic measuring means.
With the above mentioned arrangement, the present invention as defined in claim 1 enables the spectral transmittances of a lens under examination to be measured easily and promptly by utilizing the optical path of the measurement optical system of the lens.